Implantable medical device with reduced migration capabilities

Abstract

Medical devices and methods for making and using a medical device are disclosed. An example medical device may include a stent that comprises a first covered region formed of one or more interwoven filaments and a covering. The stent may also comprise a second uncovered region adjacent the first covered region. The second uncovered region may include a knitted filament. A first end of the knitted filament may be attached to the first covered region. The knitted filament is configured to be unraveled to remove both the first covered region and the second uncovered region of the stent while the first end of the knitted stent remains attached to the first covered region.

What is claimed is: 
     
       1. A stent comprising:
 a first covered region formed of one or more interwoven filaments and a covering; and 
 a second uncovered region adjacent the first covered region, wherein the second uncovered region includes a knitted filament; 
 wherein a first end of the knitted filament is attached to the first covered region; 
 wherein a second end of the second uncovered region, opposite the first end, includes a free end of the knitted filament; 
 wherein pulling the free end results in unraveling of the knitted filament to remove both the first covered region and the second uncovered region of the stent while the first end of the knitted stent remains attached to the first covered region. 
 
     
     
       2. The stent of  claim 1 , wherein the one or more interwoven filaments of the first covered region include a plurality of braided filaments. 
     
     
       3. The stent of  claim 1 , wherein the one or more interwoven filaments of the first covered region include a knitted filament. 
     
     
       4. The stent of  claim 3 , wherein the knitted filament of the second uncovered region and the knitted filament of the first covered region comprise a single knitted filament. 
     
     
       5. The stent of  claim 1 , wherein the first end of the knitted filament is attached to the first covered region at a first attachment point. 
     
     
       6. The stent of  claim 5 , wherein the first attachment point is a weld configured to terminate the unraveling of the knitted filament beyond the first attachment point. 
     
     
       7. The stent of  claim 1 , wherein the knitted filament of the second region includes a second end, and wherein the second end is attached to an intermediate portion of the knitted filament at a second attachment point. 
     
     
       8. The stent of  claim 7 , wherein the second attachment point is a weld configured to separate from the intermediate portion of the knitted filament. 
     
     
       9. The stent of  claim 1 , wherein the second uncovered region of the stent is configured to permit tissue ingrowth therein so as to reduce migration of the stent. 
     
     
       10. The stent of  claim 1 , wherein the first covered region is configured to prevent tissue ingrowth along the first covered region of the stent. 
     
     
       11. The stent of  claim 1 , wherein the first covered region, the second uncovered region, or both have a flared end portion. 
     
     
       12. The stent of  claim 1 , wherein a portion of the knitted filament extends through a plurality of interstices defined between adjacent filaments of the one or more interwoven filaments of the first covered region, and wherein the first end of the knitted filament includes a slip knot. 
     
     
       13. The stent of  claim 12 , wherein unraveling the knitted filament causes the slip knot to tighten around the end of the first covered region, and wherein the end of the first covered region collapses radially inward upon tightening of the slip knot. 
     
     
       14. A stent comprising:
 a first covered region formed of one or more interwoven filaments and a covering; and 
 a second uncovered region adjacent the first covered region, wherein the second uncovered region includes a knitted filament; 
 wherein a first end of the knitted filament is attached to the first covered region; 
 wherein the knitted filament is configured to be unraveled to remove both the first covered region and the second uncovered region of the stent while the first end of the knitted stent remains attached to the first covered region; 
 wherein the knitted filament of the second region includes a second end, and wherein the second end is attached to an intermediate portion of the knitted filament at a second attachment point; 
 wherein the second attachment point is configured to separate from the intermediate portion of the knitted filament; 
 wherein separating the attachment point from the intermediate portion of the knitted filament permits the unraveling of the second uncovered region of the stent. 
 
     
     
       15. A stent, comprising:
 a tubular member having a first end and a second end and a lumen extending therein; 
 a first covered portion disposed along the first end of the tubular member, the first covered portion including one or more interwoven filaments forming a tubular structure; 
 a second uncovered portion disposed along the second end of the tubular member; the second uncovered portion adjacent to and attached to the first covered portion; 
 wherein the first covered portion is configured to prevent tissue ingrowth along the first covered portion; 
 wherein the second uncovered portion is configured to permit tissue ingrowth therein so as to reduce migration of the stent; 
 wherein the second uncovered portion includes a knitted filament configured to be unraveled to remove both the first covered portion and the second uncovered portion of the stent while the knitted filament of the second uncovered portion remains attached to the tubular structure of the first covered portion; and 
 wherein the knitted filament of the second uncovered portion is attached to the first covered portion at an attachment point configured to terminate the unraveling of the knitted filament beyond the attachment point. 
 
     
     
       16. The stent of  claim 15 , wherein the one or more interwoven filaments of the first covered portion includes a plurality of braided filaments. 
     
     
       17. The stent of  claim 15 , wherein the one or more interwoven filaments of the first covered portion and the knitted filament of the second uncovered portion form a single knitted filament. 
     
     
       18. The stent of  claim 15 , wherein the second uncovered portion includes a single knitted filament that is distinct from any of the one or more interwoven filaments of the first covered portion.